I don't go through life verbalizing what I feel.

I want to keep on the move, keep stimulated and challenged.

Armstrong described the lunar surface as 'beautiful.' I thought to myself, 'It's not really beautiful. It's magnificent that we're here, but what a desolate place we are visiting.'

In Mars, we've been given a wonderful set of moons where we can send continuous numbers of people.

It's time to open the space frontier to citizen explorers.

Because of his military service, Dad was buried in Arlington National Cemetery.

Did the Pilgrims on the Mayflower sit around Plymouth Rock waiting for a return trip? They came here to settle. And that's what we should be doing on Mars. When you go to Mars, you need to have made the decision that you're there permanently. The more people we have there, the more it can become a sustaining environment. Except for very rare exceptions, the people who go to Mars shouldn't be coming back. Once you get on the surface, you're there.